Service-meter for telephone-lines.



No. 776,429. PATENTED NOV. 29, 1904.

V G. E. SGRIBNER.

SERVICE METER FOR TELEPHONE LINES.

APPLICATION FILED APR. 9, 1900 N0 MODEL.

uZi'lorne y.

UNITED STATES Patented November 29, 1904.

PATENT OFFICE.

CHARLES E. SCRIBNER, OF CHICAGO, ILLINOIS, ASSIGNOR TO WESTERN ELECTRICCOMPANY. OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SERVICE-METER FOR TELEPHONE-LINES.

SPECIFICATION forming part of Letters Patent No. 776,429, dated November29, 1904.

Application filed April 9, 1900- To all whom it may concern.-

Be it known that I, CHARLEs E. SCRIBNER, a citizen of the United States,residing at Chicago, in the county of Cook and State ofIlli-- bycurrents of different character than that for which the instrument isdesigned, particularly such as calling-currents 1n the line.

To this end the invent1on comprlses amaln actuating-magnet for theservice-meter and means for applying a continuous or steady current forexciting it and an auxiliary locking-magnet constructed in any suitableway to be responsive to such currents only as are not designed tooperate the register, such as the calling-currents in the line, andcontrolling a catch or other locking device for maintaining the positionof the armature of the actuating-magnet unchanged during the presence ofsuch current in the line.

The invention is illustrated in the attached drawing, which representsdiagrammatically a telephone-line extending between a substation and acentral office, a call-bell, telephones, and a service-meter orconnection-register at the substation and means at the central ofiicefor applying to the line either a current for ringing the bell or acurrent for operating the service-meter.

The appliances at the substation and at the central ofiice, with theexception of the service-meter, are of usual and well-known character.The line conductors 1 and 2 are provided at the substation with acircuit through a polarized call-bell a and a condenser 60. Atelephone-supporting switch (0 controls a cir- Serial No. 12,107. (Nomodel.)

cuit through the receiving-telephone a? and transmitting-telephone a toclose a bridge of the line-circuit, including these instruments in shuntof the bell and condenser. At the central office the line conductors areconnected with the poles of a battery Z) or other source of current, oneof the line conductors leading through the magnet of a line-signal 0.The connection of the line conductors with the battery is controlled bya cut-off relay (Z. A spring-jack e is furnished for the line, with twoline-springs which form normally open terminals of the line conductorsand an insulated test-ring which constitutes the normally open terminalof a branch conductor 3, grounded at one terminal, which includes themagnet of the cut-off relay. Pairs of plugs f and f are provided foruniting lines by means of their spring-jacks, two of the three contactsof each of the two plugs forming the terminals of the plug-circuit45 67, which is connected with the battery 6 through the windings of arepeating-coil g. The remaining contactpieces of the two plugsconstitute terminals of conductors 8 and 9, respectively, leading fromthe battery 5, which include supervisory signals h and h, referring tothe plugs f and f. These signals are controlled by supervisory relaysiand d, included in conductors 6 and 7 of the plug-circuit, each beingin this position responsive to current which is determined by thetelephone-switch of the line with which the plug is connected. Theserelays control the signals associated with the plugs by means of shuntsabout the signals. A calling-key 7c is interposed in the plug-circuitfor breaking the circuit between the plugs f and f and applying thepoles of a generator Z of alternating or pulsating current to theline-contacts of plug f.

The service-meter at the subscribers station consists of a main oractuating magnet m, a centrally-pivoted armature m, a permanent magneton for constantly polarizing the armature, a locking-magnet a and anarmaturen therefor, a catch controlled or carried by the armature 02/,arranged to engage a part carried by the armature m, and a train ofcounting mechanism with an escapement or verge connection with thearmature m. The magnet on may be connected serially in the circuit withthe telephones. The magnet 71 may be connected in multiple with themagnet m. The cores of magnet 172 should be surrounded by copper sheathsto prevent the quick response of the magnet to varying currents.

For operating the service-meter thus disposed to register calls from thesubstation which attain response at the central oflice the connectionsof the answering-plug f with the battery Z) are made in a reverse mannerfrom those of the plug f with the same battery, so that when theanswering-plug is inserted into a spring-jack of the line it applies tothe line a current of the opposite polarity to that which is produced inthe line by the insertion of the calling-plug f. Taking the telephonefrom its switch for use at the subscribers station permits the closureof the circuit of the line through the telephones and the magnets of theservice-meter. The battery I) thereupon produces a current in thecircuit which excites the line-signal c and indicates the call to theattendant. The flow of current from battery 6 through theactuating-magnet of the meter draws the armature 072/ into one positionpreliminary to actuating the wheel-train to register the use of thetelephone. The force of the retractile spring acting upon the armatureof magnet n is so adjusted that the current from the battery I) shallfail to operate it or shall at least hold it so feebly that the superiorforce of magnet m may move the armature m in spite of the slighttendency of magnet n to lock it. hen now the operator in answering thecall inserts the answeringplug in the spring-jack of the calling-line,the polarity of the current in the line is reversed, the main magnet mdraws its polarized armature m into its alternate position, and thusmoves the counting-train to register the answered call. W'hen connectionis made with the line shown in response to a call from a differentline-that is, when the line provided with the service-meter is calledfor-the plug f applies to the line the same polarity of current as thatwhich flows normally in the line at the mere taking of the telephone.Hence the establishment of connection with the line when it is calledfor leaves the service-meter in its normal position, in which it doesnot register the connection. If, however, on hearing the ringing of thebell at the station when a line is being called by the operator by meansof the calling-key in applying a pulsating or alternating current to theline, the called subscriber should take his telephone for use, thecalling-current will find circuit through the telephone-bridge andthrough the magnets on and a, connected therewith. My present inventionaims particularly to prevent or avoid the operation of the service-meterunder such circumstances. The ringing current is of greaterelectromotive force than that of battery b, besides being of rapidlyintermittent or alternating character. This ringing-current acting onthe magnet n throws the armature into vibration, whereby the catchcarried by the armature is moved into the path of the armature m at eachpulsation of current. Being of lower impedance, the magnet n receives agreater proportion of the impressed varying current than the magnet on,and the magnet on being by reason of the copper sheath'about its coresor other means for preventing the quick charging of its cores ismagnetized to a smaller extent by equal current. These differences incharacteristic action of the magnets m and a permit the magnet 72 tolock the armature m, and thus to prevent the movement of thecountingtrain.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. The combination with a service-meter and a circuittherefor, of means at the central station for applying currents ofdifferent character, an actuating-magnet responsive to all suchcurrents, a counting mechanism associated therewith, and ablocking-magnet adapted to prevent the actuation of the countingmechanism, said blocking-magnet being responsive to current of one kindonly, substantially as described.

2. In a service-meter the combination with a counting train, of anactuating magnet therefor constructed to respond sluggishly to varyingcurrent, and a locking-magnet adapted to lock the armature of saidactuating-magnet in position capable of quick response tocalling-currents through it, both of said magnets being connected withthe circuit of a telephone-line, said locking-magnet being unresponsiveto the normal steady currents of the line, as described.

3. The combination with a telephone-circuit, a call-bell in the circuit,telephones and a telephone-switch and a circuit through the telephonesclosed by the telephone-switch, and means for applying in thetelephone-circuit either varying calling-current or steady current ofeither polarity, a service-meter having two magnets, both connected withthe circuit through the telephones to be closed by the telephone-switch,one of said magnets being adapted for response to steady currents, andbeing adapted to actuate the counting mechanism, and the other of saidmagnets being constructed for quick response to callingcurrents and toremaininactive when traversed by the steady currents of the line, and alatch controlled by said quick-responding" magnet adapted to lock thearmature of the other magnet in place, and means for imparting permanentpolarity to the armature of the actuating-magnet, substantially asdescribed.

* 4. The combination with a telephone-line extending from a substationto a central of-ice,

of a connection-register having a polarized actuating-magnet connectedwith the line-circuit, means at the central office for applying varyingcurrent and steady current to the line, 5 devices connected with theline at the substation adapted for operation by such currents, and anelectromagnetic locking device at the substation responsive to thevarying currents and arranged to block the mechanism of the Iconnection-register, to prevent the operation thereof, said lockingdevice being constructed to remain inactive under the influence of thenormal steady currents in the line.

In Witness whereof I hereunto subscribe my name this 9th day ofFebruary, A. D. 1900. 5

CHARLES E. SCRIBNER.

Witnesses:

ELLA EDLER, DUNCAN E. WILLETT.

